Florida Gov. Rick Scott made perhaps the most significant statement in years Friday when it comes to Republicans and gun control, calling on his state legislature to ban the sale of semiautomatic guns to anyone under 21 years of age. Suddenly, a proposal President Trump and a couple of GOP senators have floated is supported by the Republican leader of one of the country's biggest states -- and traditionally a very pro-gun state at that.

The proposal was quickly dismissed by Democrats as a half-measure, but in context it's big. And that's mostly because it ups the ante for the National Rifle Association — and forces it into an increasingly uneasy choice.

The NRA has for years stood in the way of basically any new gun regulation, arguing that even one would be slippery slope toward the confiscation of guns. Its chief, Wayne LaPierre, this week went so far as to argue that the organization's foes don't just want to get rid of the Second Amendment, but to “eradicate all individual freedoms.”

Before Scott's announcement, the NRA signaled new age limits were out of the question. “Raising the age is not going to solve psychosis,” NRA spokeswoman Dana Loesch told CNN. Another spokeswoman said Wednesday: “Passing a law that makes it illegal for a 20-year-old to purchase a shotgun for hunting or [an] adult single mother from purchasing the most effective self-defense rifle on the market punishes law-abiding citizens for the evil acts of criminals.” (Federal law already prohibits those under 21 from buying handguns.)

But with Scott having acted, Trump still flirting with new gun laws (including age limits), and a growing number of corporations joining the #BoycottNRA movement, the NRA's hard line is being tested.

Does it stand in the way of Scott's legislative push and face a potentially high-profile loss — in the very state where the Marjory Stoneman Douglas High School tragedy happened? In Scott, they have a unique foe in a wealthy outgoing governor who is expected to run for Senate. Normally you'd expect them to primary someone like Scott, but he's got too much stature and doesn't really need money from them or their donors.

And he's not the only unwieldy figure leading the GOP's internal gun debate; even more so than Scott, Trump would be an extremely difficult foil for the NRA. As I wrote Friday, Trump is arguably the one figure in recent GOP history who could make the NRA regret having picked that fight; his ability to bring the GOP base along with him on key proposals is without recent compare. The real question is whether Trump actually follows through and pushes some kind of new gun laws. And just like we're all left to guess whether he actually will, so is the NRA.

Update: After Trump conspicuously didn't mention gun control Friday, he on Saturday morning retweeted his own tweet calling for raising the age limit and "comprehensive" background checks.

The problem with a hard-line stance is that it's undermined the second you give an inch. It's worked well for years for the NRA, causing almost the entire congressional GOP to avoid even dipping a toe in something the NRA wouldn't approve of. But once toes are being dipped — as they clearly are today — you have to make good on your zero-tolerance policy or look like you're weak.

The NRA has signaled that age limits are not okay, and now Scott has defied it. He's now officially testing its resolve. If it softens its position on age limits, it'll look weak. If it goes after Scott and loses, it'll look weak. If it goes hard after Scott and resists the change, it could have an even bigger PR problem on its hands — not to mention the prospect that Trump could join with Scott and amplify that problem exponentially.

The NRA has been among the most successful lobbying organizations in Washington for many, many years. And now, it's being tested like it simply hasn't in quite some time.